Apparatus for treating hydrocarbons



Feb. i3, 1923, 1,445,433

` S. L. GARTLAN APPARATUS FOR TREATING HYDROCARBONS Original Filed Oct. 28, 1921 Patented Feb. i3, i923.

U N i T f srs STEPHEN LOUIS GARTLAN, O TORONTO,

MASA@ ONTARIO, CANADA, ASSIGNOR F FIFTY- FIVE ONE-HUNDREDTHS T0 ALBERT EDWARD GOODERHAM, OF TORONTO, ON-

TAR/IO, CANADA.

APPARATUS FOR TREATIN G HYDROCARBONS.

Application led October 28, 1921, Serial No. 511,042. Renewed January 8, 1923.

To ZZ tc/Lom 'it may concern:

Beit known that l. STEPHEN Loris Gaur- LAN, a citizen of the United States of merica, residing at the city of Toronto. in the county of York and Province of Ontario.

Dominion of Canada, have invented certain new and useful Improvements in Apparatus for Treating Hydrocarbons; and, I hereby declare that the following is a full, clear. l0 and exact description of the same.

It is known that a natural tellin-ic hydrocarbon is a mixture of substances of varying boiling points, and that each of the hydro` carbons of higher boiling points contained in such mixtures is, during the process of distillation, exposed to various degrees of temperature below its own boiling point, so long as the hydrocarbons of lower boiling points are not removed from the still, and that the'separation of these hydrocarbons by distillation is often .difficult for fractions boiling as low as 200o C., on account of the ease of partial decomposition of the higher boiling fractions at ordinary atmospheric pressure.

It is also known in the cracking of heavy oils, that `two essential factors govern largely, the reactions that take place, namely temperature and pressure, the function of increased temperature being'to break the bonds of groups that make up the complex hydrocarbon molecule, and the function of pressure which islof chief importance, being to exert an inluence onl the nature of the resulting product. Y

Broadly speaking, cracking operations have heretofore beenl divided-into two principal types; those that involve cracking at atmospheric` pressure and those that involve crackin under increased pressure.

The isadvantage of operations involving vcracking at atmospheric -pressure is the formation of relatively large volumes 'of olefins and the `tendency of the hydrocarbons to, pass. out of the reacting sphere withv a small degree otalterationrand the diiculty of obtaining cracking in any effective degree in operations operating without pres-Y sure, is that the higher temperaturescannot be attained without causing vaporization .and Wlthout`l pressure the vapors cannot be held in the heated zone. Thedegree of'cori`r pressure for order to reach the high temperatures thatare desirable in order to bring about a maxi mum of cracking, it is necessary to use correspondingly high pressures if the two phase system is to be maintained. This simultaneous uw of both high temperatures and high pressures in the same vessel is a source of danger when a large volume of liquid is heated in a single operation, as the container is apt to give Way and the great volume of highly heated liquid then becomes a serious mena ce. i i

Operations of the above nature are also subject to the limitation common to all two phase systems namely, that the temperature 'and pressure cannot beU varied independently of each other. This .fixed interdependence of temperature and pressure has heretofore been one of the greatest handicaps of -all two phase'` systems, for the higher tem` peratures and pressures, favorable vfor cracking the lighter and intermediate fractions,

cannot be attained in large operations because of. the difficulty of finding retainers 'that will withstand'the necessary strain.

By conducting the vaporization at approximatelyatmospherlc pressure and con- .tinuously .withdrawing the vapors from the vaporizing'zone, acontinuous evolution of the vapors can be malntained attempera- Vtureswhich will permit of the vapors passing from the vaporizing zone with but a @minimum alteration of the original hydro- -tzarlgoriy molecules, and then,v by bringing these vapors todafavorable temperature, the cracking operation canL be carrled on 1n a lseparate apparatusc with i' maximum effi-- ciency under controllable conditions of tem- '30' the vaporizer indicates that the maximum perature, pressure, and subsequent release of pressure for the sudden expansion of the compressed vapors, and Will insure substantially all of the evolved vapors being broken down into the desired product.

lTo this end the vaporizing and cracking operations, are divided into distinct but iny vaporizing stage. As a consequence, a large volume of liquid may be heated and thel maximum vaporization may be attained in a single operation Without danger of the container giving Way, and lWithout danger of the large volume of highly heated liquid becoming a serious menace. And further thetemperature andl pressure during the vaporizing stage can be so controlled that the evolved vapors Will pass from the vaporizing zone With but a minimum alteration of the bonds of groups that/ make upy the original hydrocarbon molecules and the vaporizatioii, under these conditions, may be continued until an excessively` low pressure in vaporization has been attained. These vapors after passing from the ,vaporizing zone, can be brought to a temperature, favorable to their alteration during the second or cracking stage by increasing, and maintain`f ing the temperature attained during the vaporization, either before or during the period when the cracking pressure is exerted on them, and the pressure during the cracking stage may be varied to meet the requirements of the reaction and afterwards released for the sudden expansion o-f the compressed vapors. This regulation of the temperatures and pressures employed during the vaporizing and cracking stages gives control to a large extent, of the nature of the resulting product and the percentage of the original hydrocarbon treated which can be converted into the resulting product.

This invention therefore, relates to a cracking operation consisting of distinct but interdependent stages by which the vaporization of hydrocarbons, particularly telhiric hydrocarbons, and the alteration of the original hydrocarbon molecules to form resulting products of different specific gravity and boiling points to the hydrocarbon vaporiz'ed may be continuously carried on in safety and with maximum efficiency, and it consists essentially of conducting the vaporization under favorable conditions of temperature at atmospheric, or plus or minus atmos-v pheric pressure, the degree of variation`in either -direction from zero being negligible' and the heat applied during the vaporizing period being so regulated as to maintain a continuous evolution of vapors without appreciably alterin the bonds of groups that make u the original hydrocarbon molecules; withdrawing t-he evolved vapors from the vaporizing zone during the vaporizing period, increasing, and maintaining, the temperature of the vapors attained during the vaporizationto a degree favorable to the cracking stage of the operation; compressing the vapors under controllablev conditions ofy temperature and pressure and releasing the pressureafter compression for'their sudden expansion and the alteration of the original hydrocarbons into liquefied resulting products of different specific gravity and boiling points to the hydrocarbon treated.

The objects of the invention are :-.-to enable., the vaporization to be carried onl at relatively low temperatures` and under such conditions of pressure as will facilitate the iapid evolution of the vapors with but slight alteration of the original hydrocarbon molecules; to effect the alteration of these molecules by a controllable regulation of temperatuie and pressure, followed byrelease of pressure and suddenexpansion to fo-rm a resulting product of a different specific' Within the vaporizing sphere and the elementof failure of the apparatus -resulting from high pressures duiing the vaporizatioii.

In arryingout these objects a suitable vaporizng apparatus is employed in whi-cla large volume of hydrocarbon matter can be exposed'to heat. A steam generator may be connected with the vaporizing apparatus for the inject-ion of steam into the hydrocarbon or hydrocarbon vapors during the vapori/,ing period to increase the degree and rate of vaporization., A super-heater may be connected with the vaporizing apparatus to raise the teniperatnre of the vapors to a. degree favorable to the cracking stage of the opera-tion. A compressor. suitably jacketed for heating and coolingpurposes, is con-v nected directly with the. vaporizing apparatus and with the superheater foi'. continuously -ivithdrau'ing the evolved vapors from and maintaining a diminished pressure avitliin the vaporizing zone and superheater and compressing the vapors under conditions of heat exchange favorable to the requiremeiits of the reaction. and au expanyorated consists of a 50 H. l. tubular and heavy Mexican crude petroleum hydrocarbons have been vaporized by boiling the mass-at temperatures ranging from 980 C. to 415o C. and the vapors have been altered into other hydrocarbon fractions with acompressor operating at pressures up to 1500 pounds, and at temperatures up to 550O C. during the compression, the pressure after compression bein-g released for the sudden expansion of the vapors.

' The drawing is a diagrammatic view of a suitable arrangement of apparatus by which the operation may be effectively carried out.

ln the practical operation of the invent-ion it has been found that the following method and apparatus produce satisfactory results both as regards yields ot the desired hydrocarbon products and economy of operation, but other apparatus of any usual or approved type may be substituted for that hereinafter described and the spccitic temperatures and pressures may be varied to the character or conditions of thc hydrocarbons treated. f

The plant in which this process was elabtype boiler 8 for steam' generatingv purposes connectedI--to an engine 16 which drives the compressor 5: to the steam coil 3 of the superheater 2; the compressor 5. The superheater 2 is' an oil fire heated box ot' brick construction containing two sets of coils 3 and t Jfor superhcating the steam trom the boiler, and the vapor from the still or vaporizer.

The superheater is provided with a burner or burners 25 connected with a fuel supply by a pipe 26, and these burners are supplied with a steam jet from the steam pipe line 15.

rlhe vaporizer l is of cylindrical construction of a total volume ot' approximately 100 gallons and is provided withtemperature and pressure recording instruments. nect'ed with 'it is one ot the steam lines from the s uperheater and two vapor lines` one of the vapor lines leading through the superheater to the compressor. The compressor. provided with temperatme and pressure recording instruments. is ofthe three stage type. having an outer jacket such as is commonly used for cooling purposesand has a capacity of twelve cubic fectper minute. at 110 R. P. M. The compressor is connected with the intake 18 ot the expansion chamber 1T, through a needle valve 19. /and both compressor and expansion chamber are capable of withstanding high pressures. The expansion chamber 17 consists of a steel cylinder with a total volume ot about 2% cubic feet. and is capable of withstanding high pressures up to 'approximately 2,000 pounds.`

The cooler 21 is of the usual spiral type consisting of about thirty feet of one and one quarter inch coiled pipe and the receivand tothe outer jacket of' (lon-v ing tank 23 is of thirty gallon capacity and capableof withstanding' pressures up to 300 pounds.

The liquid hydrocarbons to be'treated are introduced into the vaporizer 1 which is provided with burners 12 connected by a pipe line 13 with the source of fuel supply and when oil is used as fuel the lburners are also connected by a pipe line 15 with the steam coils 3 of the superheater 2, the steam flowing through the pipe line 15 to the burners atomizing the-oil and spraying it, under pressure, through the burner outlets. The vaporizer 1 takes the form of a cylindrical still. but it may take the form of an apparatus of any othlr design whiclr will provide for the continuous evolution of a relatively large volume of vapors and may be charged and run in batches ora number of them may be connected with one or more compressors. and run simultaneously, or a number of them may be connected in series and run simultaneously, the oil circulating in the latter case from one to anotherrof the series; or it may take the form of a tube or set ot' tubes ot' similar vaporizing capacity. and in an apparatus of tubular construction, satisfactory results may be obtained by continuously injecting the oil into the tube or series of tubes suitably' heated to continuously evolve vapor.

ln the construction shown in the drawings, the vaporizer provided with two valve controlled vapor pipes 0 and leading from the vaporizing zone, the valve controlled pipe G directly4 connecting the vaporizer with the compressor at the usual intake port on the low pressure cylinder and conducting the vapors directly from the vaporizer to the conn'nessor 5. and the valvey controlled pipe 7 conducting the vapors from the vaporizer to the coil 4 ot lthe superhezllter 2. and then/to the valve controlled pipe, between its valve G and the intake port of the compressor 5. To minimize the drop in temperature between the vaporizer or super-l heater and the compressor. the pipesy G and 7 may be suit-ably covered with heat insulating material. The steam coil 3 in the s'uperhcater 2'is connected with the steam generator Q and supplies super-heated steam to the vaporizer through the steam pipe 10.

'I`o facilitate the cracking of the vapors it is necessary toJuaintain the `compressor at a temperature Jfavorable to the maximum cracking efficiency. ln treating Texas t'uel oil thefcompressor was preheated toa temperat'ure up to 550G (Y and this temperature was maintained for the compressor during the evolution ot the vapors of those fractions evolved by boiling the mass at tenperatures between 124o C. and 4000 C. lVhen the temperature'ot the mass tor the evolution ot the vapors ot the higher boiling fractions exceeded -L00O C., it was `found end of this coilorjacket is connected with.

the main steam pipe line 9 by a valve controlled steam pipe l1, and with the steam coil 3 in the superhea-ter 2 by a valve con-y trolled pipe 15. v,

Steam circulates from the steam boiler through the valve controlled pipe l5 and superheater, to the jacket of the compressor to externally preheat the'compressor before the vapors are evolved in the vaporizer. In the treatment of the Texas fuel oil previously mentioned the compressor was maintained at a temperature of about. 550D C. during the compression of the hydrocarbon fractions vaporizing at or below 4:00O C. lVhen the boiling temperature of the mass attained 40()El C., the steam from` the sluierheater to the coil or acket of the compressor was cut oft', and when the boiling temperature of the mass exceeded 4000 C., the steam circulated from the steam generator by means of the `pipe lines-9 and 11, to the compressor and effected a heat exchange .or

reduction of temperature of the compressor to about 450 C., the temperature of the compressor at all'times being controlled to the requirements of` the cracking temperature of the vaporsbeing compressed. fVhen it is necessary to effect a considerable re- `duction in the temperature of the compressor, suitable mechanical cooling means may be connectedmvith the compressor for that ini-pose.

Connected Withthe intake 1S of the expansion chamber 17 and theexit of the high pressure cylinder of the compressor is a vapor line 20, and this high pressure vapor -line is covered with suitable insulating materialto minimize the drop in temperature. The expansion chamber is provided With a gauge glass so that the apparent condition and the rate of collection o'f the liquefied vapors may be observed. Vhen the oil is introduced into the vaporizer, steam pressure is raised in the steam generator to about 100 pounds and the burners in the superheater are lighted and so regu lated as to superheat the steam from `the generator and the vapor passing from the vaporizer through lthe superheater to the compressor to a temperature up to 550 C.

SteamA from the superheating coil 3 is then conducted `through the coil or acket of the compressor to p'reheat the compressor to approximately the same temperature. The burners in the vaporizer are no iv lighted and the temperature raised until vapors are evolved. The evolution of the vaporsmay be, continued until an excessively low pressure in the vaporizer indicates that the maximum veporization of the oil introduced into the vaporizer has been attained. When the vapors begin to be evolved, the coinpressor is started and the vapors are Withdrawn by the compressor fromithe vaporizer through the vapo-r coils 4 of the superheater. The temperature of the superheater is so regulated as to heat the vapors or the loa7 boiling fractions, before compression, to a tempera-ture of about 550D C. which is found to be favorable to the cracking stage of the operation.

When the vapors passing through the superheater pick up sufficient lheat to keep the compressor at the proper operating temperature, the superheated steam to the coil or jacket of the compressor is turned off.

' Vhen the tempera-ture of the hydrocarbon inthe vaporizer reaches the maximum boiling point before cracking, the vapors are conducted direct from the vaporizer tothe compressor. When the temperature of the compressor exceeds 550O C. Wet steam from` the steam generator is turned into the coil or jacket through the pipes 9,'and 11. The introduction of this Wet steam intothe coil or jacket of the compressor has the effect of reducing the temperature of the coinpressor, thereby preventing an abnormal rise in its temperature, due t-o the' high temperature of the vaporsof the higher boiling fractions and any heat developed by the compression.

Instead of ,using the superheater to preheat the vapors passing from the'vaporizer to the compressor, the temperature of the compressor can be raised to a degree which will permit of the vapors passing direct from the vaporizing zone to the pressure zone at the vaporizing temperature and being heated by the compressor to the required degree 'for the cracking stage of the operation.

The temperature of the vaporizer is so regulated as to maintain a continuous evolution of the vapors and the speed of the compressor is so regulated as to continuously Withdraw the vapors vfromthe vaporizing Zone and maintain in it a normal pressure at or about atmospheric pressure, the degree of variation from atmospheric pressure in either direction being negligible. The lov1 pressure in the vaporizer facilitates the rapid evolution of the vapors; vitenables the vaporization to be carried on at relatively low temperatures; it eliminates the risk of dan-` ger resulting from high pressures Withiny the vaporizing sphere; and it eliminates the danger of failure ofthe apparatus resulting `from high pressures. y

The. vaporization of they liquid is started at a relatively 10W temperature to vaporize the hydrocarbon fractions of `low boiling point ranges, each' fraction as it isvaporized being drawn oif from the vaporizer bythe compressor, which act-ion of the compreor maintains in the vaporizer a normal atmosf pheric pressure or pressure varying but little above or below atmospheric pressure.

When the vapors of the low boiling fractions have been evolved and withdrawn .from the vaporizr, the temperatures of thevaporizerV and its contents are increased to continue the vaporization of the higher boiling fractions, the continuous Withdrawal of these vapors being maintained by the compressor and the operation being continued until an excessively low pressure in the vaporizer indicates that the maximum vaporization has been attained.

When the'vaporizing temperature reaches 200 C., superheated steam may be introduced into the vaporize-r and the mixture of vapors and steam is drawn off by the compressor through the superheater: The pressure in the high pressure cylinder is regulated to the requirements-of the cracking operation and may vary from 100 pounds to 1,500 pounds or more per square inch. When the temperature of the mass for the evolution of the vapors reaches 4000 C. the passage of the mixture of vapors and steam through the superheater may be discontinued and vapors may then be conducted directly to the compressor from the vaporizer.

. The operation of the compressorvis regulatedv tojgive any required pressure in the high pressure-cylinder. A practically constant flow ofcompressed vapors isv maintained through the needle valve into the expansion chamber where the pressure is immediately reduced to or within a few pounds of atmospheric pressure. ,During the compression the temperature of the vapors willv approximate 550 C., and this temperature and the prenre are maintained until the delivery of the vapors through the needle valve into theexpansion chamber, where the vapors aresuddenly expanded. The sudden expansion of the vapors causes a great drop in temperature and the liquefaction lof all but the very lightest vapors. The strain onthe vapors caused by the high temperature and pressure inthe compressor and the sudden expansion and'great drop of pressure in the expansion chamber results in the alte-ration of the bonds of groups that makeup the original hydrocarbon lmolecules, and the ,formation of bc/nds of groups which Ymake up hydrocarbon molecule/s of different specific gravity and boiling-'points or, in other words, this arrangement 'of heat control, compression, and expansion, brings into use and. renders possible the close control of the two well recognized factors made use of in the cracking of hydrocarbons, i. e.,

temperature and pressure, and bringsA intoA operation an additional factor, i. e., the principle of subjecting the hydrocarbon mole- Jcules to great strain by expansion.

For the condensation of those vapors not liquefied in the expansion chamber, the intake end of the cooler 21 is connected with the outlet 22 of the expansion chamber 17 and this cooler 21 discharges'i/nto the receiver 23 where all liqueiied vapors are collected, the differential pressure between the expansion chamber and receiving tank permitting of the unimpeded circulation of the liquefied products to the latter.` In this way everything except some of the permanent gases is collected in the receiving tank in the formof liquid of different boiling points and specific gravity to those of the original hydrocarbon treated.

It has been ascertained in the practical operation ofthis method of treating hydro- .,carbon oils such as heavy paraiiin base or asphaltum base crude oils, containing practically I'io natural naphtha, that yields as high as 3,1% of gasolene have been obtained on a single run on the batch System.

It will be understood that the above menmerely set forth as one specific example of the practical application of the process and that they may be varied to meet the requirements off the operating conditions of a commercial plant.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is l. The hereindescribed cracking apparatus for the production of lower boiling hydrocarbons comprising means for vaporizing the hydrocarbon mass at about atmospheric pressure, means for continuously withdrawing the vapors from the vaporizing zone (hiring thevaporizing period and compressing all 'off them under regulable conditions ofpresslire, and means for releasing the pressure after compression for the sudden expansion and liquefaction of the vapors to .pressure after compression for the sudden expansion and liquefaction of the vapors to form a resulting product ldiffering in speciic gravity and boiling points from the hydrocarbon vaporized.

3. The hereindescribed cracking apparatus for the production ot' lower boiling hydrocarbons comprising ymeans for vaporizing the hydrocarbon mass at about atmospheric pressure, means for continuously withdrawing the vapors from the vaporizing zone during the vaporizing period and compressing all of them under regulable conditions ofthe hydrocarbon mass at about atmosphericy pressure, means for withdrawing the vapors from and maintaining a pressure of about one atmosphere in the vaporizing .zone con.- tinuously during the vaporizing periodl and then compressing all ofthe vapors, means Jfor releasing the pressure after compression for the sudden expansion and liquefaction of the vapors to form a resulting product diftering in speci-fic gravity and boiling points from the hydrocarbon vaporized, and means for regulating the temperature of `the evolved vapors on passing from the vaporizing zone to a degree favorable tothe compression and subsequent expansion.

5. The hereindescribed cracking apparatus for lthe production of lower boiling hydrocarbons comprising means for vaporizing the hydrocarbon mass at vabout atmospheric pressure, means for compressing all the evolved vapors, means for expanding them after compression and means for regulating the temperature of the vapors on passing from the vaporizing zone to a degree favorable to the alterationl of the bonds of groups that make up the original hydrocarbon molecules to form a resulting 'product differing-in specific gravity and boiling points from the hydrocarbon vaporized.

, 6. The hereindescribed cracking apparatus for the production of lower boiling hydro- `carbons comprising-means for .vaporaing the hydrocarbon inass, means for withdrawing the vapors from the vaporizing zone and continuously maintaining in it a pressure ot about one atmosphere and compressing all the vapors on passing from vthe vaporzing zone, and means for releasing the pressure after compression for the sudden expansion and liquefaction lof the vapors.

7. The hereindescribed cracking apparatus vfor the production of lower boiling hy- .f

drocarbons comprising means for vaporizing the `lliydiiocarbon mass' at about atmospheric pressure, means for increasing and main'- taining the temperature oi the evolved va-l pors on passing from the vaporizing zone to a degree favorable to the cracking loperation,` K means for withdrawing the vapors fromhthe yaporizing4 zone and compressing p all of them, and means for releasingthe pressure pheric pressure, means independent of theV vaporizing means Jfor regulating the temperature of the evolved vapors to a degree favorable to the cracking operation, means for withdrawingvthe vapors from the vaporizing zone and compressing all of them, and

`means for releasing the pressure for the sudiden expansion of the vapors after compression.

9. The h'ereindescribed cracking apparatus for the production of lower boiling hydrocarbons comprising means for vaporizing "the hydrocarbon mass at about atmospheric pressure, `means for regulating the temperature of the vapors, after passing from the vaporizing zone, to the requirements of the cracking' reaction, means for withdrawing the vapors from the vaporizing .Zone and compressing all of them, and means for releasing the pressure after compression for the sudden expansion and liquefaction of the vapors.

10. The hereindescribed crackingv apparatus for the productionof lower boiling hydrocarbons comprising means for vaporizing the hydrocarbon mass at about atmospheric pressure, a superlieater for raising the temperature of lthe vapors after passing from the vaporizing zone 'to the requirements of the react-ion, meansfor ,compressing all of the vapors, and means for releas- 'iiig the `pressure after compression forwtlie suddenexpansion and liquet'action ,of the 11. Thehereindescribed cracking apparatus for the production of lower boiling hydrocarbons comprising means for vaporiz'- ing -the hydrocarbon mass, means for superheating the vapors of the low. boiling fractions laterv passing from 'the vapori'zing zone, a compressory for withdrawing the vapors from the vaporizingfzone and maintaining in it\=a pressure of about. one atmosphere and compressing all of .the'vapors, means regulating the temperature of the compressor to a degree favorable toztli'e reaction, and means .for releasing the `pressure after compression for the sudden expansion and liquefacrtion of the vapors.;A

drocarbons comprising lmeans for Vaporizingtlie hydrocarbon mass at about fatmosphe'ric pressure, 'asuperheater fori-increasing the temperature of the yvapors of the low iai boiling fractionson passing `frein thevaporizing zone, av compressor for withdrawing the vapors from the vaporizing zone and I p compressing all of them, means for regulatvapors from the vaporizing zone to the presa sure zone.

14. A cracking apparatus for the production of lower boiling liquid hydrocarbons comprising means for vaporizing liquid hydrocarbon, means for transferring all the evolved vapors from the vaporlzmg zone to a separate pressure zone and meansfor com-A pressing them in said separate pressure zone, and means for heating the transferred vapors'at will before the compression to a degree favorable to the alteration.

15. A cracking apparatus for 'the production of lovver boiling lliquid hydrocarbons comprising means for vaporizing liquid hy- `drocarbon, means for transferring all thel evolved vapors from the vaporizing zone to a separate pressure zone and .means for compressmg them 1n said separate pressure zone, and means .on the transfer line between the vaporizing zone and pressure zone for heating the transferred vapors at-Will to a degree favorableto the alteration.

' 16. A cracking apparatus for the production of lower boiling liquid hydrocarbons comprising means for vaporizing liquid hy- 'drocarbon` means for transferring all the evolved vapors from the vaporizing zone to a separate pressure zone and means for compressing them in said separate pressure zone, and means for heating the transferred v'apors at will before and during the compression to a degree favorable to the alteration.

lZ. A cracking apparatus for the production of lower boiling liquid hydrocarbons comprising means for vaporizing liquidy hydrocarbon, heated means for transferring all \the evolved vapors from the vaporizing zone to a separate pressure zone and Vmeans for compressing all the transferred vapors in said separate pressure Zone under controlla- .ble conditions of pressure an-d means for releasing the compression for the sudden expansion of the compressed vapors.

18. A cracking apparatus 'for the production of lower boiling liquid hydrocarbons.

comprising means for vaporizing liquid hydrocarbon, heated means for transferring all the evolved vapors from the vaporizing zone to a separate pressure zone and means for compressing all the transferred vapors in said separate pressure zone under controlla-- ble conditions of temperature and means for releasing the compression for the sudden expansion of the compressed vapors.

19. A cracking apparatus for the productidn `of lower boiling liquid hydrocarbons conprising means for vaporizing liquid hydrocarbon, heated means for transferring all the vapors from the vaporizing zone to a separate pres-sure zone and means for compressing all the transferred vapors in said separate pressure zone under controllableconditions of temperature and pressure and meansI for releasing the compression for the sudden expansion of the compressedvapors. 2D. A cracking apparatus for the production of lower boiling liquid hydrocarbons comprising means for vaporizing liquid hydrocarbon, means for transferring all the vapors to a separate pressure zone and compressing all the transferred vapors in said separate pressure zone, means for releasing the pressure after compressionffor the sudden expansion' of the vapors, and means vfor regulating the temperature of the transferred vapors at will, to the requirements of the reaction, during the transference of' said vapors from the vaporizing zone to the pressure zone.

' Washington, D. C., October 26th, 1921.

STEPHEN LOUIS GARTLAN. 

